Although he was tired, he kept on working.

虽然他很累，但他继续工作。

Unless you work hard, you will fail.

除非你努力工作，否则你会失败。

When he was young, he studied in America.

他年轻时在美国学习。

Where there is a will, there is a way.

有志者事竟成。

I used to be afraid of the dark.

我过去常常怕黑。

How do you study for a test？

你怎么为考试而学习？

By making vocabulary lists/ By asking the teacher for help.

通过制作词汇列表/通过向老师寻求帮助。

这些句子涵盖了不同的语法结构和表达方式，适合九年级学生学习和使用。建议学生在日常练习中多使用这些句子，以提高英语综合能力。